I've been wanting to cosplay a super heroine (like wonderwoman, x-men or supergirl) or villianess. But I'm kinda chubby, so I don't want anything skin tight (unless the character is curvier) or my stomach showing. If shes got hips and boobs I could probably work with skin tight (I my corsets)

I'm open to other suggestions too, video games, anime, ect. I would just prefer the above.

I'm G/H cup so no crosplay. I'm open to wigs, body paint, just about anything. I also love a challenge so tougher costumes are welcome

I've seen some Harleys over the years that used corsets and not small women pulled that look off quite brilliantly. I could also see you pulling off a Curvy Black Canary! Powergirl is also known for her very pronounced Hips and Breasts, but that outfit is very skintight, so it might not be quite what you want. Just some ideas, hope it helps.

As common as it may seem, Lulu is a great option and you seem to have pale, pretty skin an da defined jawline for that kind of outfit. I second Aoman's suggestions also. I think any of those would be great on you. A Black Widow variation isn't a bad option either.

These are somewhat simpler cosplays than challenges, but you can consider cosplaying Tsunade from Naruto and the Sorceress from Dragons Crown (game). I have to agree that Harley Quinn would also be a good pick and you get to use a corset!

Why not Poison Ivy? The traditional cosplay that I've been seeing is corset-based. She is usually a curvy character, whom people cosplay regardless of their body shape.

My friend did a Poison Ivy cosplay last year for our SuperHero/Villian day at Sakura Con. She has a larger bust size, and the costume worked out perfectly! It was a green corset with ivy, vines attached to it. Then she wore fishnet tights, and green ruffled shorts to match.
Honestly, bigger busts are easier to work with since many Animes/ Comics have women with HUGE chests! Just add a corset into whatever costume you decide for some extra shape/ lifting power!